Signal generators are electronic devices that generate repeating or non-repeating electronic signals in either the analog or digital domains. Signal generators are also known variously as function generators, radio frequency (RF) and microwave signal generators, pitch generators, arbitrary waveform generators, digital pattern generators and frequency generators. They are generally used in designing, testing, troubleshooting, and repairing electronic or electroacoustic devices.
There are many different types of signal generators, with different purposes and applications (and at varying levels of expense). RF and microwave signal generators are used for testing components, receivers, and test systems in a wide variety of applications including cellular communications, WiFi, WiMAX, GPS, audio and video broadcasting, satellite communications, radar and electronic warfare. RF and microwave signal generators normally have similar features and capabilities, but are differentiated by frequency range. RF signal generators typically range from a few kilohertz to 6 GHz, while microwave signal generators cover a much wider frequency range, from less than 1 MHz to at least 20 GHz. Some models operate at frequencies as high as 70 GHz with a direct coaxial output, and up to hundreds of gigahertz when used with external waveguide source modules. RF and microwave signal generators can be classified further as analog or vector signal generators.
It can be advantageous for RF and microwave signal generators used in measurement instruments for testing components at cellular sites to be broadband, portable and relatively low power. However, generating low band frequencies from high frequency oscillators can be difficult, expensive, and power hungry, and can result in signals too noisy for use in sensitive applications. Instruments including, but not limited to, vector network analyzers (VNAs) can benefit from improved systems and methods for generating low band frequency sine waves.